How evolution turned us into liberals and conservatives

Do you ever find yourself reading something by a commentator you disagree with and wanting to punch them in the face? Do you listen to people on the other side of the political debate and find yourself almost hating them? As a metropolitan conservative, and so permanently behind enemy lines in the culture war, I’ve become conscious down the years of being considered almost an enemy by people who might otherwise like me; as the German soldiers say in the films, vithout ze war ve might haf been friends, ja?

The culture war is far more vicious in the United States, and has become more so in recent years, something that has grown to disturb the University of Virginia Professor Jonathan Haidt. His book, The Righteous Mind, might cool tempers and make us aware of why we are how we are. I found it so therapeutic that I didn’t shout at the Today programme for, maybe, three days. Tom Chivers has also been reviewing the book from his own, liberal, perspective here.

A self-identified liberal, Haidt seeks to understand, using evolutionary psychology and anthropology, why some people become liberals and others conservatives, and why their moral frameworks are different, arguing that they shouldn’t seek to demonise each other. (As he explains, he uses liberal in the modern sense, to mean Left-liberal, and he later looks at “Right-liberals”, also known as classical liberals or libertarians, who are separate to true conservatives.)

Humans, as Haidt says, are nine-tenths chimpanzee and one-tenth bee. Unlike other large primates, we have developed a hive mentality that allows us to work in very large, non-kin related groups, and this partly explains our instinct towards tribalism – whether it’s to our countries or ethnic groups, religious communities, political parties or sports teams. We have deep-rooted instincts towards defending and protecting our group, and we have also evolved morality for the same purpose, including looking out for freeloaders within.

This moral system has allowed us to evolve in ever larger communities and it is these instincts, not reason, that directs our morals and our politics. As he writes: “Anyone who values truth should stop worshiping reason. We all need to take a cold hard look at the evidence and see reasoning for what it is.”

The human mind is divided, Haidt argues, into two parts, a rider and an elephant, and the rider’s job is to serve the elephant. “The rider is our conscious reasoning – the stream of words and images of which we are fully aware. The elephant is the other 99 per cent of mental processes – the ones that occur outside of awareness but that actually govern most of our behaviour.”

Intuition comes first, strategic reasoning second, and this goes the same for intelligent and dim alike. Education and IQ makes no difference to where the elephant goes, only to how well the rider explains its actions.

Since the conscious mind’s job is to justify the choices it has made, we are prone to confirmation bias, seeing what it wants us to see, and our mind treats contradictory evidence as a threat. In 2004 psychology professor Drew Westen used functional magnetic resonance imaging to look at the brains of 15 Democrats and 15 Republicans. When initially shown information that damaged their party candidate’s reputation, he writes: “The threatening information (their own candidate’s hypocrisy) immediately activated a network of emotion-related brain areas – areas associated with negative emotion and responses to punishment.”

In contrast there was no increase in activity in the dorsolateral prefrontal cortex (d1PFC), the main area for cool reasoning tasks: “Whatever thinking partisans were doing, it was not the kind of objective weighing or calculating that the d1PFC is known for.”

When shown a second video, which exonerated their candidate “the ventral striatum started humming – that’s one of the brain’s major reward centres. All animal brains are designed to create flashes of pleasure when the animal does something important for its survival, and small pulses of the neurotransmitter dopamine in the ventral striatum (and a few other places) are where these good feelings are manufactured. Heroin and cocaine are addictive because they artificially trigger this dopamine response.”

Being proved correct provides us with a dopamine hit, which is why obsessed politicos and bloggers trawl the internet looking for anything to prove them right.

“If this is true,” says Haidt: “then it would explain why extreme partisans are so stubborn, closed-minded, and committed to beliefs that often seem bizarre or paranoid. Like rats that cannot stop pressing a button, partisans may be simply unable to stop believing weird things. The partisan brain has been reinforced so many times for performing mental contortions that free it from unwanted beliefs. Extreme partisanship may be literally addictive.”

So what makes some people conservative and others liberal? Haidt is big on group selection (which was virtually killed off in academia in the 1970s but is hugely popular at the moment) and uses it to argue that we have been bred to be more moral, but only in a limited way. Oxytocin, the “love hormone”, is responsible for producing “parochial altruism”; surveys of people playing group games showed those sprayed with oxytocin were more likely to play altruistically towards members of their own group, “but they showed no concern at all for improving the outcomes of men in the other groups”. In another study oxytocin “caused Dutch men to like Dutch names more and to value saving Dutch lives more”. Curiously, they found no sign that increased in-group love was paired with increased out-group hate, which rather goes against the popular idea that exclusive patriotism leads to xenophobia.

Along with a colleague he looked at the adaptive challenges that stood out for human beings during recent evolution, to form six moral foundations. These were caring for vulnerable children, forming partnerships with non-kin to reap the benefits of reciprocity, forming coalitions to compete with other coalitions, negotiating status hierarchies, and keeping oneself and one’s kin free from parasites and pathogens. These formed the five moral foundations – care, fairness, loyalty, authority and sanctity. A sixth foundation, liberty/oppression, they added later.

Where people differ is that self-identified liberals care far more about three of them – caring, liberty and fairness (which actually means reciprocity and equity rather than distribution). The Left’s championing of traditional underdogs, in particular, whether it’s women, ethnic minorities, gays, the disabled or animals, appeals to their instinctive opposition to oppression, and their desire to care.

These are, obviously, good things, but liberals fail to understand that their opponents also share these desires, but weigh them against competing ideas about loyalty, hierarchy and sanctity, all of which are vital for moral capital (that is the degree to which a community possesses shared values, virtues and institutions, and is able to regulate selfishness and ensure co-operation without the use of coercion).

Why do they think differently? One of the reasons may be mundane, and rather depressing. A DNA analysis of 13,000 Australians found that liberals and conservatives had some marked difference in genes that related to neurotransmitter functioning, particularly glutamate and serotonin, both of which are involved in the brain’s response to threat and fear.

Conservatives react more strongly to signs of danger, including threat of germs and contamination, and even white noise. Liberals have more genes implicated in receptors for dopamine, which is associated with sensation-seeking and openness to experiences. Other papers have found a few other traits, but nearly all are related to threat sensibility or openness to experience.

That might be why actors, rock stars and basically everyone who’s remotely cool or sexually magnetic votes Democrat or Labour, and are prone to making idiotic, ill-informed comments about the world. While conservatives tend to be, on average, more fearful, unimaginative, unadventurous and, who knows, probably sexually inadequate too.

Haidt started out a liberal; indeed he began looking at this subject because, as a Democrat, he saw that his party failed to connect with most ordinary Americans, who did not share its metropolitan liberal distaste for faith and flag. But by the end of the book it’s clear that he’s become sympathetic to conservative philosophy, the idea “that people are inherently imperfect and are prone to act badly when all constraints and accountability are removed”; and that “our reasoning is flawed and prone to overconfidence, so it’s dangerous to construct theories based on pure reason, unconstrained by intuition and historical experience”.

Or maybe that’s just my brain working its confirmation bias, looking for the next political dopamine hit.